Michael S (already5chosen@yahoo.com) on 8/6/10 wrote:
---------------------------
>AM (myname4rwt@jee-male.com) on 8/6/10 wrote:
>---------------------------
>>none (none@none.com) on 8/5/10 wrote:
>>---------------------------
>>>I picked the one which claims x300 speedup.
>>>
>>>http://www.opticsinfobase.org/oe/abstract.cfm?uri=oe-17-22-20178
>>>
>>>"In comparison,we compiled the CPU implementation, tMCimg,
>>>using the “-O3” option with the gcc compiler and double-
>>>precision computation on a single core of an Intel 64bit Xeon
>>>processor of 1.86GHz."
>>>
>>>So single core, low frequency, double precision, out-of-the
>>>box compilation. Enough said.
>>
>>They got these results using a card available (new) for $80+ these days http://www.google.com/products?q=9800+GT&scoring=p
>>
>>> (8800GT no longer avail, 9800GT uses the same G92 chip).
>>
>>Apparently, $80 won't buy you even the cheapest new Core 2 Duo, let alone a 1.86 GHz Xeon, which can cost as little as $188 (E5502) or as much as $3157 (L7555) http://www.intc.com/priceList.cfm
>
>That's stupid argument. Video card can't do anything on its own.

But neither can any CPU. Right, you can't run a system w/o a CPU, so to make the argument valid we should adjust for the price of the cheapest CPU. But even then, the $45 delta (cheapest Celeron) is just enough to shift to the cheapest Core 2 Duo. Keep in mind that component costs (PCB, RAM, all the supporting circuitry) work against the GPU, and do so to a larger extent when low-cost hw like said 9800 GT is considered.

In general, it would be ridiculous to discount the price argument as inessential (except for theoretical research) since as long as there are codes for GPU and CPU doing the same thing, the smarter buy is one that costs less for the req'd performance.

It needs at least
>$400 PC that includes (for Intel platform) at least $43 CPU (meet E3300, dual-core,
>2.5 GHz, but small cache and slow bus). So for $70 more you can get $113 E7500 which
>is quite decent 2.93 GHz dual-core with 3MB cache and 1066 FSB and still buy some
>beer on remaining 10 bucks. Or, switch the whole platform to core-i3 and for the
>same $113 get i3-530 - another 2.93 GHz dual-core but with bigger cache and no FSB bottleneck.
>
>Of course, if you have parallel code running on you CPU than buying dual-core makes
>little sense from price/performance perspective. Its much smarter to invest another
>$170 (< 50% increase if you look at the price of the whole system and not just a
>CPU) and get $284 i7-860 - 2.8GHz quad-core with HT, turboboost, 8MB L3 cache. Or,
>if you found HT not helpful, you can get exactly the same chip with HT permanently
>disabled now called i5-760 for just $205.
>
>And those just Intel options. AMD offers even more GFLOPs/$.
>Like Phenom II X6 1055T - six 2.8 GHz cores for $199.
>Or Phenom II X4 945 - four 3.0 GHz cores for $149.
>Or, on the low end, X3 720 - three 2.8 GHz cores that I can't find on official
>price list, but with the street prices as low as $99.